Compilare: main.cpp: In function 'int main()': main.cpp:12:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("paranteze2.in", "r", stdin); ^ main.cpp:13:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("paranteze2.out", "w", stdout); ^ main.cpp:17:26: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fgets(s, NMAX, stdin); ^ main.cpp:20:9: warning: 'ch' may be used uninitialized in this function [-Wmaybe-uninitialized] if(ch == '(') ^~